scholarly journals Comparative study of Chemical Pathology sample collection tubes at the largest hospital in South Africa

2021 ◽  
Author(s):  
Siyabonga Khoza ◽  
Sarah Ford ◽  
Ernest Buthelezi ◽  
Donald Tanyanyiwa
Keyword(s):  
South Africa ◽  
Lactate Dehydrogenase ◽  
Aspartate Aminotransferase ◽  
Sample Collection ◽  
Time Intervals ◽  
Paired Samples ◽  
Reference Change Value ◽  
Percentage Difference ◽  
Heparin Plasma ◽  
The Stability

Background: BarricorTM lithium heparin plasma tubes are new blood tubes that have been introduced to overcome the effects of gel in serum separator tubes (SST) and the shortcomings of standard lithium heparin plasma. We aimed to evaluate BarricorTM tubes as an alternative to serum separator tubes and compare the stability between the tubes. Methods: Forty-four paired samples were collected using both BarricorTM and SST. We compared five analytes at baseline (<6h) and after every 24h using the Passing-Bablok and Bland-Altman plots. Aspartate aminotransferase (AST), potassium (K), phosphate (PO4), lactate dehydrogenase (LDH), and creatinine were analysed in both tubes. We calculated the percentage difference for each analyte between the baseline and time intervals to assess analyte stability. The percentage difference was compared to the desirable specification for bias and reference change value (RCV). Results: All analytes were comparable at baseline. Statistical differences (p<0.001) became evident after 24h. PO4, K, and creatinine had a mean difference that exceeded the desirable specification for bias (-9.59%, -9.35%, and -4.59%, respectively). Potassium was stable up to 24h in both tubes. LDH showed better stability in SST (144h vs. 96h). PO4 concentrations were more stable in both tubes with the SST (96h vs. 72h). Creatinine and AST had the longest stability in both tubes compared to other analytes (144h). Conclusions: Data demonstrated variability and similarities in analyte concentrations and stability, respectively in both tubes

Production and certification of secondary enzyme reference materials (ERMs). Part 1: Preparation of the sera and some of their properties.

1986 ◽  
Vol 32 (10) ◽  
pp. 1901-1905 ◽  
Author(s):  
J C Koedam ◽  
G M Steentjes ◽  
S Buitenhuis ◽  
E Schmidt ◽  
R Klauke
Keyword(s):  
Creatine Kinase ◽  
Lactate Dehydrogenase ◽  
Reference Material ◽  
Human Serum ◽  
Dehydrogenase Activity ◽  
Aspartate Aminotransferase ◽  
Alanine Aminotransferase ◽  
Glutamate Dehydrogenase Activity ◽  
The Stability ◽  
Clinical Enzymology

Abstract We produced three batches of a human-serum-based enzyme reference material (ERM) enriched with human aspartate aminotransferase (EC 2.6.1.1), alanine aminotransferase (EC 2.6.1.2), creatine kinase (EC 2.7.3.2), and lactate dehydrogenase (EC 1.1.1.27). The added enzymes were not exhaustively purified; thus the final ERMs contained some enzymes as contaminants, of which only glutamate dehydrogenase activity might interfere. The stability during storage and after reconstitution was good. The commutability of the four enzymes in the three ERM batches was also good, except when German or Scandinavian methods for aminotransferases were involved. The temperature-conversion factors for the ERMs were equivalent to those for patients' sera. Reactivation after reconstitution was complete within 5 min and was independent of the temperature of the reconstitution fluid. We believe that these secondary ERMs will aid in the transfer of accuracy between well-defined reference methods and daily working methods so that clinical enzymology results will become more comparable from laboratory to laboratory.

Measurement of aspartate aminotransferase activity: effects of oxamate.

1979 ◽  
Vol 25 (4) ◽  
pp. 555-559 ◽  
Author(s):  
R Rej
Keyword(s):  
Lactate Dehydrogenase ◽  
Aspartate Aminotransferase ◽  
Potent Inhibitor ◽  
Side Reactions ◽  
Mitochondrial Enzyme ◽  
Measurable Effect ◽  
Human Origin ◽  
Aminotransferase Activity ◽  
The Stability ◽  
Inhibited Enzyme

Abstract Oxamate, a potent inhibitor of lactate dehydrogenase, is shown also to inhibit aspartate aminotransferase activity, both in human serum and in purified isoenzymes of human origin. The inhibition was competitive with respect to 2-oxoglutarate for both isoenzymes. The apparent Ki was 29 mmol/L for the cytoplasmic enzyme and 17 mmol/L for the mitochondrial enzyme. Noncompetitive inhibition was found between oxamate and aspartate. At saturating concentrations of substrate (2-oxoglutarate greater than or equal to 15 mmol/L, L-aspartate greater than or equal 150 mmol/L) oxamate inhibited the mitochondrial enzyme but had less effect on the cytoplasmic isoenzyme. Oxamate at 40 mmol/L inhibited the enzyme in serum by 11 and 9% in assays containing 2-oxoglutarate at 6.7 and 15 mmol/L, respectively. This concentration of oxamate inhibited enzyme activity in serum by 5% more than did the same concentration of Cl- (itself an inhibitor). Oxamate (less than or equal to 30 mmol/L) had no measurable effect on the stability or activity of porcine malate dehydrogenase. Until the effects of its inhibitory properties are considered, addition of oxamate to suppress lactate dehydrogenase-mediated side reactions in the assay of aspartate aminotransferase cannot be recommended.

Time-related changes in the diagnostic utility of total lactate dehydrogenase, lactate dehydrogenase isoenzyme-1, and two lactate dehydrogenase isoenzyme-1 ratios in serum after myocardial infarction

1990 ◽  
Vol 36 (7) ◽  
pp. 1317-1322 ◽  
Author(s):  
L V Galbraith ◽  
F Y Leung ◽  
G Jablonsky ◽  
A R Henderson
Keyword(s):  
Myocardial Infarction ◽  
Lactate Dehydrogenase ◽  
Likelihood Ratio ◽  
Roc Curve ◽  
Operating Characteristic ◽  
Negative Likelihood Ratio ◽  
Diagnostic Utility ◽  
Time Intervals ◽  
Dehydrogenase Isoenzyme ◽  
Cardiac Care Unit

Abstract Using receiver-operating characteristic (ROC) curve and likelihood ratio analysis, we examined the diagnostic utility of total lactate dehydrogenase (LD; EC 1.1.1.27) activity (I). LD isoenzyme-1 activity (II), and the LD-1 percentage of total LD activity (III), LD-1 LD-2 (IV), and LD-1/LD-4 (V) in 347 persons admitted to the Cardiac Care Unit (of whom 173 were subsequently proven to have had myocardial infarction). Blood was sampled from these subjects at about 6-h intervals for up to 96 h from the onset of chest pain. Defining an "effective" test as one having an area under the ROC curve of greater than or equal to 0.9, we determined the ranked utility (greatest to least) of these tests as V = IV greater than III greater than II greater than I. Tests III, IV, and V had by this criterion, diagnostic effectiveness equivalent to measurements of creatine kinase-2 in serum but in samples obtained at later time intervals. The decision thresholds for both high (constant) test sensitivity and specificity varied with time, to differing extents, over the entire 96-h period, a finding with important diagnostic implications. We document positive and negative likelihood ratio values for each of these tests throughout the entire period of study.

scholarly journals An Evaluation of the Stability of Mould Flux Properties in the Process of Continuous Steel Casting

2017 ◽  
Vol 62 (2) ◽  
pp. 885-889 ◽  
Author(s):  
J. Falkus
Keyword(s):  
Process Parameters ◽  
Liquidus Temperature ◽  
Casting Process ◽  
Continuous Steel Casting ◽  
Time Intervals ◽  
Equal Time ◽  
Industrial Experiments ◽  
Mould Flux ◽  
Steel Cast ◽  
The Stability

AbstractThis paper presents research on the mould slag formed on the basis of two mould fluxes. In the conducted industrial experiments, slag was sampled in equal time intervals between adding subsequent portions of mould flux. The research focused on the an evaluation of the stability of slag parameters by assessing the change in its liquidus temperature. It was shown that a mould flux needs to be assessed individually taking into account the casting process parameters and the steel cast grade.

scholarly journals Color stability of ceramic brackets immersed in potentially staining solutions

2015 ◽  
Vol 20 (4) ◽  
pp. 32-38 ◽  
Author(s):  
Bruna Coser Guignone ◽  
Ludimila Karsbergen Silva ◽  
Rodrigo Villamarim Soares ◽  
Emilio Akaki ◽  
Marcelo Coelho Goiato ◽  
...  
Keyword(s):  
Profile Analysis ◽  
Artificial Saliva ◽  
Rocky Mountain ◽  
Color Stability ◽  
Bonferroni Correction ◽  
Time Intervals ◽  
Significance Level ◽  
Paired Samples ◽  
Immersion Period ◽  
Ceramic Brackets

OBJECTIVE: To assess the color stability of five types of ceramic brackets after immersion in potentially staining solutions.METHODS: Ninety brackets were divided into 5 groups (n = 18) according to brackets commercial brands and the solutions in which they were immersed (coffee, red wine, coke and artificial saliva). The brackets assessed were Transcend (3M/Unitek, Monrovia, CA, USA), Radiance (American Orthodontics, Sheboygan, WI, USA), Mystique (GAC International Inc., Bohemia, NY, USA) and Luxi II (Rocky Mountain Orthodontics, Denver, CO, USA). Chromatic changes were analyzed with the aid of a reflectance spectrophotometer and by visual inspection at five specific time intervals. Assessment periods were as received from the manufacturer (T0), 24 hours (T1), 72 hours (T2), as well as 7 days (T3) and 14 days (T4) of immersion in the aforementioned solutions. Results were submitted to statistical analysis with ANOVA and Bonferroni correction, as well as to a multivariate profile analysis for independent and paired samples with significance level set at 5%.RESULTS: The duration of the immersion period influenced color alteration of all tested brackets, even though these changes could not always be visually observed. Different behaviors were observed for each immersion solution; however, brackets immersed in one solution progressed similarly despite minor variations.CONCLUSIONS: Staining became more intense over time and all brackets underwent color alterations when immersed in the aforementioned solutions.

scholarly journals Local myotoxicity of ketamine hydrochloride in the marmoset

1987 ◽  
Vol 21 (1) ◽  
pp. 60-67 ◽  
Author(s):  
C. W. Davy ◽  
P. N. Trennery ◽  
J. G. Edmunds ◽  
J. F. B. Altman ◽  
D. A. Eichler
Keyword(s):  
Creatine Kinase ◽  
Lactate Dehydrogenase ◽  
Physical Properties ◽  
Aspartate Aminotransferase ◽  
Solution Ph ◽  
Histopathological Findings ◽  
Plasma Enzyme ◽  
Routine Blood ◽  
Ketamine Hydrochloride ◽  
Injection Procedure

An investigation of raised plasma aspartate aminotransferase (AST) in marmosets after intramuscular ketamine injection suggested a local myotoxicity. This was confirmed by a range of histopathological findings from myofibrillar striation loss to necrosis. In addition to the elevations in AST levels, creatine kinase and the lactate dehydrogenase-5 isoenzyme levels were elevated. It was further demonstrated that, although the physical properties of the injectable solution (pH, osmolality) and to a lesser extent the injection procedure itself caused slight changes in plasma enzyme levels, the ketamine was predominantly responsible for the lesion. No hepatic interactions were seen. This effect should be taken into consideration when this anaesthetic is used in the marmoset if the primary objectives of the experiment entail routine blood analyses.

THE DEVELOPMENT OF A METHOD FOR DIRECT MASS SPECTROMETRIC ANALYSIS OF BIOLOGICAL SAMPLES USING POROUS SAMPLERS

2021 ◽  
Vol 55 (1) ◽  
pp. 99-103
Author(s):  
R.E. Levin ◽  
◽  
M.A. Shamraeva ◽  
I.M. Larina ◽  
D.S. Bormotov ◽  
...  
Keyword(s):  
Biological Samples ◽  
Biological Fluids ◽  
Storage Conditions ◽  
Spectrometric Analysis ◽  
Sample Collection ◽  
Mucous Membranes ◽  
The Status ◽  
Direct Mass Spectrometry ◽  
The Stability ◽  
Blood Spot

The paper presents a method for rapid multi-omics investigation of biological samples using polypropylene bulk porous samplers. The use of porous samplers makes it easy to collect samples from the surface of the skin, mucous membranes, and biological fluids even in a field, and the surfaces of wounds and injuries. Collected samples do not require special storage conditions, and the samplers are lightweight and very compact. They can be used to monitor the condition of cosmonauts before, during, and after the spaceflight with the same sample collection method. The analysis of biomaterial applied to the sampler is performed using direct mass spectrometry methods, similar to the dried blood spot technique that is already used in clinical practice. However, bulk porous samplers allow expanding the range of analytes ionization conditions, which increases the stability and reliability of the ionization process, which expands the variety of analyzed molecules. The proposed method can be used to study compounds of various classes, including proteins, lipids, and metabolites, to systematically monitor the status of people in extreme conditions (athletes, astronauts), or to study the condition of patients in the clinic.

scholarly journals Psittacine beak and feather disease virus in budgerigars and ring-neck parakeets in South Africa

2004 ◽  
Vol 71 (1) ◽  
Author(s):  
J. Albertyn ◽  
K.M. Tajbhai ◽  
R.R. Bragg
Keyword(s):  
South Africa ◽  
Polymerase Chain Reaction ◽  
Genetic Variation ◽  
Disease Virus ◽  
Common Disease ◽  
Sample Collection ◽  
Chain Reaction ◽  
Polymerase Chain ◽  
Feather Disease Virus ◽  
Viral Isolates

Psittacine beak and feather disease (PBFD) is a common disease of the psittacine species and is caused by the psittacine beak and feather disease virus (PBFDV). In this study the occurrence of the disease in ring-neck parakeets and budgerigars in South Africa suffering from feathering problems, using polymerase chain reaction as a diagnostic test was investigated. The genetic variation between viral isolates was also studied. Results indicate that PBFDV can be attributed to being the cause of feathering problems in some of the ring-neck parakeets and budgerigars in South Africa. Genetic variation of isolates occurs between species and individuals. A cheap and easy to use method of blood sample collection on filter paper for diagnostic purposes was also evaluated. It proved to be less stressful to the birds and did not inhibit further processes.

Exercise training increases electron and substrate shuttling proteins in muscle of overweight men and women with the metabolic syndrome

2005 ◽  
Vol 98 (1) ◽  
pp. 168-179 ◽  
Author(s):  
Dustin S. Hittel ◽  
William E. Kraus ◽  
Chuck J. Tanner ◽  
Joseph A. Houmard ◽  
Eric P. Hoffman
Keyword(s):  
Metabolic Syndrome ◽  
Lactate Dehydrogenase ◽  
Pyruvate Dehydrogenase ◽  
Oxidative Metabolism ◽  
Aspartate Aminotransferase ◽  
Aerobic Training ◽  
Exercise Intervention ◽  
Complex Iii ◽  
Men And Women ◽  
The Metabolic Syndrome

Aerobic conditioned muscle shows increased oxidative metabolism or glucose relative to untrained muscle at a given absolute exercise intensity. The studies of a targeted risk reduction intervention through defined exercise (STRRIDE) study is an aerobic exercise intervention in men and women with features of metabolic syndrome (Kraus WE, Torgan CE, Duscha BD, Norris J, Brown SA, Cobb FR, Bales CW, Annex BH, Samsa GP, Houmard JA, and Slentz CA, Med Sci Sports Exerc 33: 1774–1784, 2001), with four muscle biopsies taken during training and detraining time points. Here, we expanded a previous study (Hittel DS, Kraus WE, and Hoffman EP, J Physiol 548: 401–410, 2003) and used mRNA profiling to investigate gene transcripts associated with energy and substrate metabolism in STRRIDE participants. We found coordinate regulation of key metabolic enzymes with aerobic training in metabolic syndrome (aspartate aminotransferase 1, lactate dehydrogenase B, and pyruvate dehydrogenase-α1). All were also quickly downregulated by detraining, although the induction was not an acute response to activity. Protein and enzymatic assays were used to validate mRNA induction with aerobic training and loss with detraining (96 h to 2 wk) in 10 male and 10 female STRRIDE subjects. We propose that training coordinately increases the levels of aspartate aminotransferase 1, lactate dehydrogenase B, and pyruvate dehydrogenase-α1 subunit, increasing glucose metabolism in muscle by liberating pyruvate for oxidative metabolism and, therefore, limiting lactate efflux. Serial measurement of fasting plasma lactate from 62 subjects from the same exercise group demonstrated a significant decrease of circulating lactate with training. We also found evidence for sex-specific molecular remodeling of muscle with ubiquinol-cytochrome c reductase core protein II, a component of mitochondrial respiratory complex III, which showed an increase after training that was specific to women. These biochemical adaptations complement existing molecular models for improved glucose tolerance with exercise intervention in prediabetic individuals.

scholarly journals The influence of the drug LHS-1208 on cardiovascular system

2018 ◽  
Vol 17 (3) ◽  
pp. 70-80
Author(s):  
N. P. Ermakova ◽  
I. V. Merkulova ◽  
O. I. Konyaeva ◽  
N. Yu. Kulbachevskaya ◽  
T. V. Abramova ◽  
...  
Keyword(s):  
Lactate Dehydrogenase ◽  
Total Dose ◽  
Cardiovascular System ◽  
Anticancer Drug ◽  
Aspartate Aminotransferase ◽  
Heart Muscle ◽  
Maximum Dose ◽  
Morphological Changes ◽  
Toxicological Study ◽  
Functional Changes

Introduction.This article presents a fragment of a preclinical toxicological study of a new Russian anticancer drug derived from n-glycoside indolokarbazole LCS-1208 – study of cardiotoxicity, which is one of the specific complications of anticancer chemotherapy.Objective.Preclinical toxicological study of the effect of the drug LCS-1208 on the cardiovascular system of animals to assess its cardiotoxic effects.Materials and methods.Studies were conducted on 40 healthy non-harmless mongrel male rats and 4 dogs Beagle, male and female. The drug was administered daily 15 times to rats-intraperitoneal in total doses of 50, 100 and 200 mg/kg; to dogs – intravenously in total doses of 20 and 30 mg/kg. The period of observation of rats was 30 days, for dogs was 60 days. Changes in electrocardiogram indices, macroscopic and histological picture of heart changes and changes in biochemical parameters of enzymes activity – lactate dehydrogenase and aspartate aminotransferase were evaluated.Results.In rats LCS-1208 throughout the period of observation caused functional changes in electrocardiogram: increase in PQ and QT intervals and cardiac rhythm disturbance (loss of R wave), which indicates a violation of electrical conductivity. Morphological changes in the heart muscle were detected on the 3rd day of observation in total doses of 100 and 200 mg/kg, which remained until 30 days of observation only in animals receiving the drug in the total dose of 200 mg/kg. In some dogs for different periods of observation the drug caused functional changes in the electrical activity of the heart: an increase in the QRS interval, the inversion of the T wave, the appearance of a deep Q wave and an increase in the activity of lactate dehydrogenase and aspartate aminotransferase compared to back ground indicators. Morphological changes in the heart muscle were detected on the 3rd day of observation only in the total dose of 30 mg/kg, which persisted up to 60 days of observation.Conclusion.It was found that the new Russian anticancer drug LHC-1208, a derivative of indocarbazole N-glycoside, has a cardiotoxic effect, causing functional changes in the cardiovascular system of rats in all doses studied, and in dogs only in the maximum dose. Morphologically, cardiotoxicity is not confirmed in animals receiving a minimal dose of the drug, but only in animals receiving the maximum dose of the drug.

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